Cattle naturally avoid areas that are located far from water or that require them to climb steep slopes. This tendency causes the cattle to overgraze lowland riparian areas while ignoring abundant or high quality forage in other areas. This "localized overgrazing" causes several significant problems. First, it reduces the rancher's profit because it wastes forage. Second, the cattle trample the vegetation in resulting high-traffic areas near water sources. This increases pollution, causes erosion, and reduces stream bank stability. These effects can eventually result in watershed degradation and poor water quality. Finally, localized overgrazing prevents nutrients returned to the soil through manure from being spread to their best effect.
Increasing the natural grazing range of cattle can reduce these problems. One advantage of a large grazing range is that cattle consume forage in areas that would otherwise go unused. This allows existing acreage to support more head and can improve individual animal performance (e.g., increased body condition or higher weight gains). The resulting decrease in forage pressure on the lowland riparian areas also allows the local vegetation to grow more vigorously. This means that ranchers can maintain or even increase vegetative cover around lakes and streams. Finally, a large grazing range spreads manure over more acreage.
The prior art has suggested several methods to solve this localized overgrazing problem. These methods include fencing, herding, constructing water developments, and strategically placing salt blocks. However, all of these methods have significant drawbacks. Fencing, for example, requires that the rancher build a physical barrier to force the cattle into the underutilized areas. This requires a large capital outlay, because the rancher must build a barrier capable of holding the cattle. Fences also have significant maintenance costs, are impractical in rugged areas, and may be illegal on public land.
Water developments, like fences, are expensive to build and are impractical in rugged areas. In addition, water developments have limited effectiveness because they cannot be moved easily. This drawback often creates a new area of localized overgrazing. Finally, water developments frequently require an external power source to maintain the fluid level and may not be permitted in environmentally sensitive areas.
Herding is an expensive, short term method of extending grazing range. Herding requires that a rancher push the cattle into the underutilized rangeland areas. This process is labor intensive because the rancher must travel to the cattle's location and remain with them until they reach the desired areas. The entire process must be frequently repeated because the cattle need to return to the riparian areas for water.
The strategic placement of salt blocks has also been suggested as a tool to improve grazing distribution. However, research has shown that salt does not effectively attract cattle to the underutilized rangeland areas or encourage them to consume the forage around the salt block.
For the foregoing reasons, there is a need for a new method of extending grazing distribution so that the livestock will better utilize the existing rangeland.